JUNEAU, Alaska (AP) -- A ball. A boat. A little girl's sandal. Filmmakers are working to find - and tell - the stories behind some of the items that have washed up on North American shores following the deadly 2011 tsunami in Japan.

"Lost and Found" aims to reunite items discovered by beachcombers and others who feel compelled to return them to their rightful owners, co-director John Choi said.

A trailer for the film, which is still being produced, features two men affected by the items they've found. John Anderson found a volleyball on a beach in Washington state and Marcus Eriksen, head of an expedition that sailed from Japan to Hawaii to look for tsunami debris last year, found part of a boat. Neither of the items has been linked to their original owners yet.

"It was just like, Whoa, oh man! There's one of them balls with all the writing on it," Anderson says in the clip. "I'm more interested in the story behind it. You know, I would sure like to know what happened to these people. It would be nice to know that they survived or this was at home while they were away - just this got washed away."

Eriksen said when his team first saw the boat, there was initial excitement, "because we had been watching the ocean for a few weeks, just wondering what's out there. But when we approached this, it quickly went from fascination and excitement to, like, the sobering reality that this was someone's property, and we were very quickly filled with compassion about, you know, who lost this boat."

"They didn't lose it," he said in the clip. "It was taken from them by natural disaster, so I feel compelled to find that individual."

Monday marks the two-year anniversary of the disaster, which devastated a long stretch of Japan's northeastern coast and killed thousands of people. The Japanese government estimated that 1.5 million tons of debris was floating in the ocean in the immediate aftermath of the tsunami, but it's not clear how much is still floating.

Tsunami debris is tough to monitor and distinguish from the everyday debris - much of it from Asia - that has long been a problem along the West Coast. The National Oceanic and Atmospheric Administration said just 21 items of the more than 1,500 reports of possible tsunami debris - including balls, a motorcycle and boats - have been firmly traced back to the tsunami. However, the agency lists scores of other items along the West Coast and across the Pacific Ocean as potentially linked.

Choi first got the idea for the documentary about 1 1/2 years ago, after hearing a news report discussing a tsunami debris field. He started thinking about what might wash ashore, and how cool it would be if there was an effort to return found items.

He connected with co-director Nicolina Lanni. At the time, he said, nothing had washed ashore. The effort took off after they met Seattle-based oceanographer Curtis Ebbesmeyer, who shared his thoughts on what might happen and encouraged them in their effort.

The Canada-based filmmakers have been filming, on and off, for about a year. They established a network of contributors, and at times have been involved in trying to track down information on items found, like the little pink-and-purple sandal. A woman they met at a recent beachcomber fair found the shoe in Hawaii. A picture of it was posted on the film's Facebook page, asking for help translating the handwriting on it.

So far, he said, the team is looking at six stories, three of which involve items already traced to their owners.

"Our film is about 3 countries, 2 continents, separated by the great vastness of the Pacific Ocean coming together to share in the memories, mourn the losses and find great joy in the reuniting of something once thought to be lost forever but has now been found," a description of the project, on the Facebook page, says.

Additional filming is planned for North America this spring and Japan this summer. The filmmakers have been raising money, to help with costs.

Choi hopes to have the documentary released by the third anniversary of the disaster.